/* 清除浮动 */

.clearfix::after {
    content: "";
    display: block;
    clear: both;
    height: 0;
    zoom: 1;
    overflow: hidden;
}


/* 版心 */

.container {
    width: 1200px;
    margin: auto;
}


/* 设置左浮动 */

.fl {
    float: left;
}


/* 设置右浮动 */

.fr {
    float: right;
}


/* 按钮键 */

.open {
    background: #00ae69;
    color: white !important;
}